Rammer and extractor assembly for telescopic rounds

ABSTRACT

In cooperation with a caseless round of telescopic configuration, a longitudinally reciprocating plunger responsive to forward travel thereof moves the round projectile forwardly in the body member for insertion into the barrel bore for discharge. The plunger carries a firing pin which is spring-biased to a forward round impacting position and is driven rearwardly responsive to discharge gas pressure. A latch pivotally carried by the plunger is pivoted by the striker portion of the firing pin into engagement with a flange formed on the rear end of the projectile when the firing pin goes into its forward position and is held in engagement with the flange if the round fails to discharge thereby maintaining connection between the projectile and the plunger for withdrawal of the projectile back into the body member during rearward travel of the plunger.

United States Patent Wiese 51 Aug. 1, 1972 Inventor:

Harold H. Wiese, Davenport, Iowa The United States of America asrepresented by the Secretary of the Army July 24, 1970 Assignee:

Filed:

Appl. No.:

US. Cl. ..42/25, 102/38, 102/43,

l02/45, l02/92.4, l02/DIG. 1 Int. Cl. ..F4lc 15/00, F42b 5/18, F42b11/00 [58] Field of Search ..42/25, 16; l02/DIG. l, 38, 102/43, 45

[56] References Cited UNITED STATES PATENTS 3,439,635 4/1969 Hensley102/38 3,501,858 3/1970 Hensley et al. ..42/l6 16,797 3/1857 Hicks..42/25 R3,798 l/l870 Hicks ..42/25 FOREIGN PATENTS OR APPLICATIONS7,076 5/ 1890 Great Britain ..l02/38 Primary Examiner-Benjamin A.Borchelt Assistant Examiner-C. T. Jordan Attorney-Harry M. Saragovitz,Edward J. Kelly, Herbert Berl and Albert E. Arnold, Jr.

[ 5 7] ABSTRACT In cooperation with a caseless round of telescopicconfiguration, a longitudinally reciprocating plunger responsive toforward travel thereof moves the round projectile forwardly in the bodymember for insertion into the barrel bore for discharge. The plungercarries a firing pin which is spring-biased to a forward round impactingposition and is driven rearwardly responsive to discharge gas pressure.A latch pivotally carried by the plunger is pivoted by the strikerportion of the firing pin into engagement with a flange formed on therear end of the projectile when the firing pin goes into its forwardposition and is held in engagement with the flange if the round fails todischarge thereby maintaining connection between the projectile and theplunger for withdrawal of the projectile back into the body memberduring rearward travel of the plunger.

5 Claims, 4 Drawing Figures RAMMER AND EXTRACTOR ASSEMBLY FOR TELESCOPICROUNDS BACKGROUND OF THE INVENTION This invention relates to gunstructure for ramming the projectile in a round of telescopicconfiguration forwardly from the body member thereof and pertains moreparticularly to such a rammer adapted for use with caseless roundswhereby the projectile is withdrawn back into the body member if theround should fail to fire.

Ammunition rounds of telescopic configuration are generally foundadvantageous when space for feeding or chambering the rounds is criticalbecause thereby the rounds can be fed and chambered at their minimumlength and then extended after being chambered to locate the projectileforward of the propellant. Such configuration has been foundadvantageous, too, with caseless rounds as it eliminates the requirementfor the bodymember, formed from solid propellant material, to provideaxial support for the projectile. A problem, however, arises as to theremoval of a dud round, which is, of course, in its extendedconfiguration because the gun structure for chambering the round isadapted to accommodate it in its minimum, telescopic length.

SUMMARY OF THE INVENTION It is a principal object of this invention tomodify the projectile in a caseless round of telescopic configurationand the longitudinally reciprocating gun rammer for pushing theprojectile forwardly in the body member so that if the round should notfire the projectile is withdrawn back into the body member by the rammerduring the rearward stroke thereof.

To achieve this object the rammer plunger, which carries thereciprocating firing pin which is springbiased in its forward roundimpacting position and is driven rearwardly responsive to discharge gaspressure is provided with a pivotal latch which is pivotally displacedby the conical striker portion of the firing pin into engagement with anannular flange, formed in the rear end of the projectile, when thefiring pin goes into its forward position. The latch is held inengagement with the flange until the firing pin is actuated rearwardlyby discharge gas pressure. If the round should fail to fire, theprojectile remains connected to the plunger during its rearward strokeso as to be withdrawn thereby into the body member.

Further objects and advantages of the invention will be apparent fromthe following specification and the accompanying drawing which is forthe purpose of illustration only.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary, longitudinallycross-sectioned view of a firearm showing the structure of thisinvention with the projectile extended by the plunger and the latch inengagement with the annular flange in the base of the projectile;

FIG. 2 is a view similar to FIG. 1 but shows the projectile withdrawnback into the body member and the latch disconnected therefrom;

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 1; and

FIG. 4 is an enlarged cross-sectional view showing the cooperation ofthe latch with the annular flange in the projectile when in engagementtherewith.

DESCRIPTION OF THE PREFERRED EMBODIMENT Shown in the drawing is afirearm breech 12 provided therein with a split type chamber 14 whichopens and closes responsive to cyclic actuation of the firearm operatingmechanism (not shown) to receive a caseless round 16 for discharge.Round 16 is of a telescopic configuration and includes a projectile 18initially located within an axial bore 20 through a body member 22formed of a solid propellant material. A barrel 24 with a bore 26 isfixed to the front end of breech 12 in coaxial relationship with chamber14 and the rear end of the bore is countersunk at 28.

Extending axially from chamber 14 through the rear end of breech 12 is acylindrical hole 30 which mounts a plunger 32 for sliding reciprocationtherein in forward and rearward strokes responsive to cyclic actuationof the operating mechanism. Plunger 32 has approximately the samediameter as bore 20 in round 16 so that such plunger is insertablethereinto during its forward stroke to push projectile l8 forwardly inbody member 22 for extension into bore 26, as shown in FIG. 1. Theforward displacement of projectile 18 is limited by contact of rotatingband 34 thereon with countersunk portion 28. The front edge of rotatingband 34 is beveled at 36 to conform with countersunk portion 28 thereby,when plunger 32 moves projectile 18 forwardly, the beveled edge of therotating band is pressed against the counterbore portion to seal thefront end of chamber 14.

Formed in the rear end of projectile 18 is a cylindrical recess 38 whichis undercut to form an annular flange 40 around the mouth thereof, andlocated axially in the front end of the recess is a primer 42 which,when detonated, ignites body member 22. Primer 42 is detonated by afiring pin 44 which is terminated at the front end by a conical strikerportion 48 and which is mounted in plunger 32 by means of an axial hole46 therein for displacement between a retracted position and a forwardposition in impact against primer 42. F iring pin 44 is biased forwardlyby spring 47 and is displaced rearwardly responsive to the gas pressuregenerated by ignition of body member 22. A radial slot 50 communicateswith hole 46 and mounted in such slot is a latch 52 which is pivoted atthe rear end for displacement between an outward engaging position andan inward disengaged position. The front end of latch 52 is terminatedby a hook 54 which extends therefrom for engagement with flange 40 tolock projectile 18 to plunger 32 for displacement therewith when thelatch is in the engaging position. Hook 54 is essentially of triangularconfiguration, as shown in FIG. 4, and includes a front inclined side 56and a rear inclined side 58 both of which sides have camming cooperationwith flange 40 as hereinafter described. Formed on the front end oflatch 52, below hook 54, is a round protrusion 60 which, as shown inFIG. 1, is cammingly engaged by striker portion 48, when firing pin 44moves into its forward position, to pivot latch 52 to its engagingposition wherein hook 54 is located in front of flange 40 fortransferring rearward movement of plunger 36 to projectile l8. Latch 52is held in its engaging position by the blocking action of strikerportion 48 through the forward bias of spring 47 against firing pin 44.

OPERATION When round 16 is located in chamber 14, the chamber is closed,and firing pin 44 is retracted, firing sequence commences by the forwarddisplacement of plunger 32 which moves projectile l8 forwardly in bodymember 22 for insertion into bore 26 and which locates hook 54 forwardlyof flange 40. Contact of front side 56 of hook 54 with flange 40 assuresdisplacement of latch 52 to the disengaged position free of interferencewith the forward displacement of plunger 32. Round 16 is fired byrelease of firing pin 44, through trigger means (not shown), which ispropelled forwardly by spring 47. As firing pin 44 moves to its forwardposition, striker portion 48 has camming contact with protrusion 60thereby pivoting latch 52 outwardly to its engaging position with hook54 located in front of flange 40, as shown in FIGS. 1 and 4. Whenstriker portion 48 makes impact with primer 42 and body member 22 isignited by the detonation, the resulting gases act against the strikerportion to accelerate firing pin 44 rearwardly. During the initialretraction of firing pin 44, striker portion 48 moves away fromprotrusion 60 to free latch 52 for displacement to its disengagedposition by movement of flange 40 against rear side 58 of-hook 54 asprojectile 18 is propelled forwardly.

If body member 22 for any reason should fail to ignite, firing pin 44remains in its forward position thereby maintaining striker portion 48thereof in blocking relationship respective to latch 52. Thus, whenplunger 32 is actuated rearwardly, responsive to the cyclic actuation ofthe operation mechanism (not shown), projectile 18 is drawn back intobody member 22 and the dud round 16 is easily removed by suitableejection means from chamber 14 when opened responsive to cylic actuationof the firearm operating mechanism (not shown).

I wish it to be understood that I do not desire to be limited to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

I claim:

1. In combination with an ammunition round of telescopic configurationcomprising a body member with an axial bore therethrough and aprojectile slidingly located within said bore, a gun breech including achamber for receiving said round for discharge, and a plunger disposedfor reciprocation relative to said chamber in forward and rearwardstrokes and for insertion into said bore during the forward stroke toextend said projectile forwardly therefrom, the improvement comprising arecess in the rear end of said projectile, an annular flange around themouth of said recess, a latch carried by said plunger for releasableengagement with said flange for withdrawal of said projectile back intosaid bore responsive to movement of said plunger durmg the rearwardstroke thereof, a firing pin mounted in said plunger for longitudinaldisplacement to a forward round striking position responsive to springbiasing means and to a retracted position responsive to discharge gaspressure, and means on said firing pin disposed in cooperation with saidlatch for securing said latch in engagement with said flange when saidfiring pin is in its forward position.

2. The invention as defined in claim 1 and including means for mountingsaid latch to said plunger for pivotal displacement between an engagingposition and a disengaged position relative to said flange, a conicalstriker portion on said firing pin, a protrusion extending from saidlatch for contact by said striker portion when said firing pin isadjacent its forward position during forward travel thereof forcammingly pivoting said latch to its engaging position.

3. The invention as defined in claim 2 and including on said latch ahook arranged thereon so as to be located forwardly of said flange whensaid latch is in its engaging position for transferring displacement ofsaid plunger during its rearward stroke to said projectile forwithdrawal thereof into said bore.

4. The invention as defined in claim 3 wherein said hook includes afront inclined side cammingly contactable with said flange during theforward stroke of said plunger for displacing said latch to itsdisengaged position, and a rear inclined side cammingly contactable withsaid flange during rearward stroke of said plunger for displacing saidlatch to its disengaged position.

5. The invention as defined in claim 3 wherein said round is of thecaseless type and said body member comprises a solid propellantmaterial.

1. In combination with an ammunition round of telescopic configurationcomprising a body member with an axial bore therethrough and aprojectile slidingly located within said bore, a gun breech including achamber for receiving said round for discharge, and a plunger disposedfor reciprocation relative to said chamber in forward and rearwardstrokes and for insertion into said bore during the forward stroke toextend said projectile forwardly therefrom, the improvement comprising arecess in the rear end of said projectile, an annular flange around themouth of said recess, a latch carried by said plunger for releasableengagement with said flange for withdrawal of said projectile back intosaid bore responsive to movement of said plunger during the rearwardstroke thereof, a firing pin mounted in said plunger for longitudinaldisplacement to a forward round striking position responsive to springbiasing means and to a retracted position responsive to discharge gaspressure, and means on said firing pin disposed in cooperation with saidlatch for securing said latch in engagement with said flange when saidfiring pin is in its forward position.
 2. The invention as defined inclaim 1 and including means for mounting said latch to said plunger forpivotal displacement between an engaging position and a disengagedposition relative to said flange, a conical striker portion on saidfiring pin, a protrusion extending from said latch for contact by saidstriker portion when said firing pin is adjacent its forward positionduring forward travel thereof for cammingly pivoting said latch to itsengaging position.
 3. The invention as defined in claim 2 and includingon said latch a hook arranged thereon so as to be located forwardly ofsaid flange when said latch is in its engaging posiTion for transferringdisplacement of said plunger during its rearward stroke to saidprojectile for withdrawal thereof into said bore.
 4. The invention asdefined in claim 3 wherein said hook includes a front inclined sidecammingly contactable with said flange during the forward stroke of saidplunger for displacing said latch to its disengaged position, and a rearinclined side cammingly contactable with said flange during rearwardstroke of said plunger for displacing said latch to its disengagedposition.
 5. The invention as defined in claim 3 wherein said round isof the caseless type and said body member comprises a solid propellantmaterial.